1. Field of the Invention
This invention relates to a document processor having a function of composing a document.
2. Related Background Art
Conventionally, a simple document processor called a word processor, especially a Japanese word processor, processes any characters at a fixed pitch, so that a train of alphabet characters or a train of Japanese Kana and/or Kanji characters are processed at the same character pitch. Some processors are capable of printing English characters in a somewhat proportional manner.
On the other hand, a high-performance character processor having an electronic function of composition, for example, proposed in earlier applications by the same applicant (Ser. No. 797,831 filed on Nov. 13, 1985 and Ser. No. 935,382 filed on Nov. 26, 1986), is capable of setting a variable character pitch for each character and frame processing, so that it is capable of printing and outputting the same document as that prepared by the simple word processor.
However, if a document such as that shown in FIG. 9 and prepared by a word processor is input to a high-performance device of this type, its ruled lines and tables will be destroyed conventionally, as shown in FIG. 10. This is because the respective widths of characters of the English term "INITIAL" are composed as being variable in a proportional manner, because the number and/or position of characters contained in each line are different from those processed at a fixed pitch, and because the high- and lower-performance processors are different qualitatively in proportional processing. Other causes are that numerals and/or various brackets are processed in a manner different especially from the processing at fixed pitches and that the high- and lower-performance processors are different functionally in word wrapping. Thus conventional methods of processing only characters and codes in a simple manner cannot utilize a document, as it is, containing tables prepared by word processors. In order to prevent these problems, there is proposed a method which includes the steps of adding special-purpose control information to information input by a word processor to form a document, and inputting the document to a high-performance processor of the above type to cause the same to interpret the control information for composition. To this end, input operations other than those on the word processor must be mastered. For these drawbacks, especially in handling tables, the relationship between a Japanese word processor and a corresponding higher-performance document processor having an electronic function of composition is similar to that between an English word processor and a corresponding higher-performance document processor.